This invention relates to disposable container covers and more particularly to an improvement in the structure of container covers making it possible to securely interlock a plurality of disposable containers and container covers to form a stable stack.
Disposable containers are finding increasing use in the sale of beverages and other food products for consumption at a location other than the place of sale. For example, throw-away containers made of impregnated paper, plastic and the like materials are widely used in vending machines to contain hot and cold drinks and liquid food products such as soups and the like, as well as take-out counters of restaurants and in fast food outlets. These containers are generally of recessed-bottom, frusto-conical design and are provided at the place of sale with container covers or lids of plastic material which contain a groove that snaps over the container lip to seal it and prevent the contents within from spilling.
It frequently occurs that sales of food products in containers of the type described to one individual customer involve a plurality of containers. In such instances it is desirable to have a convenient means of carrying or transporting a plurality of containers without the risk of dropping them or spilling their contents. Thus, for example, fast food outlets generally provide the consumer with a tray prepared from a flat cardboard fold-out into which cups and other containers may be placed. However, such trays hold only the amount of containers that will fit on the tray surface and thus take up a considerable surface area compared to the containers held. In addition, the cardboard trays and the like are themselves an extra expense and also create additional disposal problems.
Recessed-bottom, frusto-conical containers of the type generally used for the disposable variety are stored, prior to use, as a stack of nested containers. See, for example, U.S. Pat. No. 3,139,213. The stacking of sealed containers designed for marketing food products and other commodities, such as conventional metal cans, on the shelves of grocery stores and supermarkets is also known. In U.S. Pat. No. 3,091,361, there is disclosed a sealed container wherein top and bottom walls are designed in such a way that they may be stacked one within the other so as to positively preclude the stacked containers from slipping laterally relative to one another. The patent discloses that the end walls of the container are designed so that a portion of one end wall may be inserted into a portion of the other end wall of a duplicate container for such stacking. The containers shown are cylindrical and may be used for marketing paints and heavy type liquids.
However, the container structure of U.S. Pat. No. 3,091,361 does not provide the most advantageous mode for stacking containers of the disposable variety which are subject to all manner of handling and not mere shelf stacking. Thus, the container of U.S. Pat. No. 3,091,361, does not provide firm interengagement between containers since the end walls that insert into one another are of a dimension such that one is smaller than the other and freely fits into it.
Thus, there has not heretofore been suggested any means for providing stable stacking of filled and covered frusto-conical disposable containers for convenient storage and carrying thereof. My invention provides such an advantage by providing a resilient container cover having a structure which permits the telescopic insertion of a portion of the container cover about the bottom of a duplicate container to tightly interengage it through the release of elastic forces within the container cover upon firm telescopic positioning.